metamorphic
Quartzite
Metamorphic Quartzite (SiO2)
Hardness of 7 on the Mohs scale, typically white, gray, or reddish in color, vitreous to greasy luster, non-foliated crystal structure, conchoidal fracture, specific gravity around 2.65.
Identified More metamorphic →
Explore Quartzite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 7 on the Mohs scale, typically white, gray, or reddish in color, vitreous to greasy luster, non-foliated crystal structure, conchoidal fracture, specific gravity around 2.65.
Formation & geological history
Formed from quartz-rich sandstone or chert through the process of regional or contact metamorphism, subjecting the parent rock to high temperatures and pressures. Geological age ranges from Precambrian to Cenozoic.
Uses & applications
Used widely in construction as crushed stone for roadbeds, railway ballast, building facades, decorative aggregate, and in the manufacturing of refractory bricks and silica.
Geological facts
Quartzite is extremely durable and resistant to chemical weathering, which is why mountains made of quartzite often stand out as high ridges in the landscape.
Field identification & locations
Can be identified in the field by its hardness (scratches glass easily), sugary texture on freshly broken surfaces, and the fact that it breaks across quartz grains rather than around them, unlike sandstone.
More like this
